Isoniazid + Pyrazinamide + Pyridoxine - instructions for use, dose, side effects, contraindications

Clinical and pharmacological group: & nbsp

Other synthetic antibacterial agents

Included in the formulation

Phthisopyram® B6

pills inwards

АТХ:

J.04.A.C.51 Isoniazid in combination with other drugs

Pharmacodynamics:

Combined anti-tuberculosis drug.

Isoniazid

Inhibits the enzymes necessary for the synthesis of mycolic acids, which are the main structural fragments of the cell walls of mycobacterium tuberculosis.

The most intensive synthesis of mycolic acids is carried out in growing cells, so isoniazid has a bactericidal action on them, and bacteriostatic action on mature cells.

The high selectivity of the chemotherapeutic effect of isoniazid is due to the fact that there are no mycolic acids in the tissues of the macroorganism, as well as in other microorganisms.

Pyrazinamide

In the body it turns into pyrazinic acid, which is active only in acidic medium (foci of caseous decay). Prevents the synthesis of mycolic acid, the main substrate of mycobacterium tuberculosis membranes.

Pyridoxine

Vitamin B₆. In the body, phosphorylation is converted to pyridoxal-5-phosphate, which is part of the enzymes involved in decarboxylation, transamination and racemization of amino acids.Prevents the development of peripheral polyneuropathy, which develops due to the impact of anti-tuberculosis drugs.

Pharmacokinetics:

Isoniazid

After oral administration, the empty stomach is completely absorbed in the gastrointestinal tract. The maximum concentration in blood plasma is achieved in 1-4 hours. The connection with plasma proteins is from 1 to 10%.

Therapeutic effect develops after the reception. Metabolism in the liver by acetylation to inactive metabolites, penetrates the placental barrier, is excreted in breast milk.

The rate of acetylation of the drug is genetically determined, so the half-life of isoniazid varies. Half-life for "fast acetylators" is 1 hour, for "slow acetylators" - 3 hours. Elimination by the kidneys.

Pyrazinamide

After oral administration, the empty stomach is completely absorbed in the gastrointestinal tract. The maximum concentration of pyrazinic acid in the blood plasma is reached after 2 hours. The connection with plasma proteins is 10-20%.

Metabolism in the liver.

The half-life is 8-9 hours. Elimination by the kidneys.

Pyridoxine

After oral administration, the empty stomach is completely absorbed in the gastrointestinal tract. The maximum concentration in the blood plasma is reached after 2 hours. The connection with plasma proteins is 90%.

Metabolism in the liver. Penetrates through the placenta, found in breast milk.

The half-life is 15-20 days. Elimination by the kidneys. It is deduced by hemodialysis.

Indications:It is used for the treatment of tuberculosis of any form and localization.

ICD-10

I.A15-A19.A18.8 Tuberculosis of other specified organs

I.A15-A19.A17 Tuberculosis of the nervous system

I.A15-A19.A15.9 Tuberculosis of respiratory organs of unspecified localization, confirmed bacteriologically and histologically

Contraindications:

Peptic ulcer of the stomach and duodenum, cardiovascular failure, epilepsy, propensity to convulsive seizures, violations of the liver and kidneys, age up to 3 years, pregnancy and lactation, individual intolerance.

Carefully:

Atherosclerosis, psoriasis, bronchial asthma, diseases of the nervous system, eczema in the phase of exacerbation, myxedema.

Pregnancy and lactation:Contraindicated during pregnancy and lactation.

Dosing and Administration:

Inside, after a meal, 5-10 mg / kg 1 time per day.

Side effects:

Isoniazid

Central and peripheral nervous system: memory disorders, insomnia, mental disorders disorders, euphoria, peripheral neuritis, muscle twitching.

The cardiovascular system: pain in the heart.

Digestive system: medicinal hepatitis.

Dermatological reactions: itching, skin rash.

Sense organs: optic neuritis - blurred vision or loss of vision.

Reproductive system: gynecomastia, menorrhagia.

Allergic reactions.

Pyrazinamide

Central and peripheral nervous system: dizziness, headache, depression, increased excitability, sleep disorders, convulsions, hallucinations.

Hemopoietic system: thrombocytopenia, porphyria, hypercoagulation.

Digestive system: a sensation of metallic taste in the mouth, vomiting, diarrhea.

Musculoskeletal system: myalgia, arthralgia, rarely - gouty arthritis.

Dermatological reactions: acne, photosensitivity.

urinary system: interstitial nephritis.

Allergic reactions.

Pyridoxine

Central and peripheral nervous system: a feeling of constriction and compression of the distal parts of the limbs - a symptom of "gloves" and "stocking."

Digestive system: heartburn.

Allergic reactions.

Overdose:

Metabolic acidosis, neurotoxic effect: dysarthria, lethargy, disorientation, hyperreflexia, convulsions, coma.

Treatment is symptomatic. Effective hemodialysis.

Interaction:

Isoniazid

Strengthens the action indirect hemocoagulants.

Inhibits the metabolism of benzodiazepines, phenytoin and theophylline.

Simultaneous use with paracetamol and other hepatotoxic substances increases the risk of toxic hepatonecrosis.

Antatsidnye means slow down and reduce the absorption of isoniazid in the intestine, it is recommended to take them with an interval of 1 hour.

With the simultaneous use of certain fish species (tuna, sardinella) and cheeses (Swiss), there may be a hyperemia of the skin, itching, headache due to the isoniazid suppression of monoamine oxidase and diaminoxidase activity in the blood plasma and a violation of the metabolism of histamine and tyramine.

Pyrazinamide

Reduces the effectiveness of antidotal drugs and increases the concentration of uric acid in the blood plasma.

Reduces the concentration and effectiveness of cyclosporine.

Special instructions:

In the treatment it is not recommended to drive vehicles and work with moving mechanisms.

Instructions

Isoniazid + Pyrazinamide + Pyridoxine (Isoniazidum + Pyrazinamidum + Pyridoxinum)